“SSL23

“SSL23_GET_SERVER_HELLO：未知协议”错误尝试访问Outlook smtp服务器(“SSL23_GET_SERVER_HELLO:unknown protocol” Error Trying to Reach Outlook smtp Server)

我正在尝试从iOS应用程序中的Outlook帐户发送电子邮件。 我正在使用Mailcore2和Outlook的Live-SDK。 我能够收到电子邮件，但在尝试发送电子邮件时收到错误：“无法建立与服务器的稳定连接”。

为了调查这个问题，我进入终端并尝试通过SSL连接：

openssl s_client -crlf -connect smtp-mail.outlook.com:587

我得到的回复是：

error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol:/SourceCache/OpenSSL098/OpenSSL098-50/src/ssl/s23_clnt.c:607

我不确切地知道这个错误意味着什么，经过一些搜索后我发现对这个问题的一个常见反应是我试图访问的服务器可能不支持必要的SSL协议。 此站点： http ： //foundeo.com/products/iis-weak-ssl-ciphers/test.cfm允许您测试为特定域启用的SSL协议。 使用这个我发现SSLV2被禁用，SSLV3也被禁用。

我不清楚所有这些意味着什么或我可能需要做什么来连接到这个服务器。 任何帮助表示赞赏。

I'm trying to send emails from an Outlook account in my iOS application. I'm using Mailcore2 and Outlook's Live-SDK. I am able to receive emails, but get an error when I try to send emails: "a stable connection to the server could not be established".

To investigate the issue, I went into the terminal and tried to connect via SSL:

openssl s_client -crlf -connect smtp-mail.outlook.com:587

The response I got back was:

error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol:/SourceCache/OpenSSL098/OpenSSL098-50/src/ssl/s23_clnt.c:607

I don't know exactly what this error means, after a bit of searching I found that a common response to this issue was that the server I am trying to reach may not support a necessary SSL protocol. This site: http://foundeo.com/products/iis-weak-ssl-ciphers/test.cfm allows you to test which SSL protocols are enabled for a particular domain. Using this I found that SSLV2 is disabled and SSLV3 is also disabled.

I not clear on what all this means or what I might need to do to connect to this server. Any help is appreciated.

最满意答案

到端口587的SMTP连接开始未加密。 如果服务器支持，可以在SMTP会话中使用STARTTLS命令稍后关闭加密。

openssl支持某些协议（包括SMTP）的STARTTLS 。 它需要-starttls smtp命令行选项，如https://stackoverflow.com/a/14645854/2139766中所述

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Outlook.com似乎不支持smtps： http ： //windows.microsoft.com/en-us/windows/outlook/send-receive-from-app

SMTP connections to port 587 starts unencrypted. Encryption may be turned out later using STARTTLS command in SMTP session if server supports it.

openssl supports STARTTLS for some protocols including SMTP. It requires -starttls smtp command line options as described in https://stackoverflow.com/a/14645854/2139766

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Outlook.com does not seem to support smtps: http://windows.microsoft.com/en-us/windows/outlook/send-receive-from-app